DARK DEFECTS IN II-VI BLUE-GREEN LASER-DIODES

The nature and origin of the nonluminescent dark defects responsible for the current rapid degradation;of II-VI blue-green laser diodes based on the ZnCdSe/ZnSSe/ZnMgSSe pseudomorphic separate confinement heterostructure have been examined by transmission electron microscopy. The dark defects observed in the laser stripe region by electroluminescence microscopy have been identified to be dislocation networks developed at the quantum well region. The dislocation networks have been observed to be nucleated at dislocations originating from pairs of V-shaped stacking faults which are nucleated at or near the II-VI/GaAs interface.